I figured as much re the point of Reachability. What I (think I) meant was that a tweak such as ReachApp - assuming I've properly understood what it does - appears to "repurpose" that function and make it so that double-tapping the home button allows you to introduce a useable second app into what I'm referring to as the "space."
Don't get me wrong, I do appreciate the response (and accept the utility Reachability is meant to provide), but given the fact that I've never personally had much use for Reachability, I went ahead and wondered whether... the manner in which the app slides down might make it possible for a future update to allow you to "run" another app simultaneously (above it).
To be honest, I held out (etc.) on owning a smartphone until about a year ago. Now that I'm all in, as it were, I'm of course realizing how spoiled I've been re being able to multitask on a, let's call it, regular computer.
Although I've come across a bunch of post-jailbreak tweaks that enable multitasking, I wanted to bring up the "issue" by way of Reachability, and a potential iOS "solution." Might not have been the most astute point of departure, in hindesignt. But for whatever reason I'm not going to jailbreak - at least not anytime soon, I don't think. (Besides, am not so sure one has been made available for the new operating system).
Apologies for rambling. Am clearly somewhat stubbornly hoping this "multitasking" thing happens (simply because I want it to?) and have no real knowledge of software and processing power and all that jazz.